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Second order advantage in the determination of amaranth, sunset yellow FCF and tartrazine by UV-vis and multivariate curve resolution-alternating least squares
(Elsevier Science, 2009-11)
A direct spectrophotometric method for the determination of three artificial colors - amaranth, sunset yellow FCF and tartrazine - in beverages samples is proposed. The spectra were recorded between 359 and 600 nm. The ...
Novel combination of non-aqueous capillary electrophoresis and multivariate curve resolution-alternating least squares to determine phenolic acids in virgin olive oil
(Elsevier, 2013-02)
This paper presents the development of a non-aqueous capillary electrophoresis method coupled to UV detection combined with multivariate curve resolution-alternating least-squares (MCR-ALS) to carry out the resolution and ...
Multi-analyte quantification in bioprocesses by FTIR spectroscopy using Partial Least Squares Regression and Multivariate Curve Resolution
(Elsevier Science, 2014-01)
This paper presents the quantification of Penicillin V and phenoxyacetic acid, a precursor, inline during Pencillium chrysogenum fermentations by FTIR spectroscopy and partial least squares (PLS) regression and multivariate ...
A down-to-earth analyst view of rotational ambiguity in second-order calibration with multivariate curve resolution: a tutorial
(Elsevier Science, 2021-04)
Rotational ambiguity is a phenomenon with the potential of generating an uncertainty in the estimation of analyte concentrations in protocols based on matrix instrumental data processed by multivariate curve resolution - ...
Multivariate curve resolution strategy for non-quadrilinear type 4 third-order/four way liquid chromatography–excitation-emission fluorescence matrix data
(Elsevier Science, 2018-11)
For the first time, a third-order/four-way system having instrumental modes depending on each other was experimentally generated and it was successfully resolved. Non-quadrilinear type 4 data, constituted by liquid ...
Colloidal gold clusters formation and chemometrics for direct SERS determination of bioanalytes in complex media
(2020-01-05)
In this work, we report the sensitive and selective sensing of the purine bases adenine and guanine in urine matrix by using surface-enhanced Raman spectroscopy (SERS) and a colloidal SERS substrate. To identify suitable ...
Dispersive liquid–liquid microextraction of quinolones in porcine blood: Validation of a CE method using univariate calibration or multivariate curve resolution-alternating least squares for overlapped peaks
(Wiley VCH Verlag, 2017-04)
In the previously published part of this study, we detailed a novel strategy based on dispersive liquid–liquid microextraction to extract and preconcentrate nine fluoroquinolones in porcine blood. Moreover, we presented ...
A novel approach based on capillary electrophoresis coupled to augmented multivariate curve resolution-alternating least-squares modeling for the determination of pKa of 2-hydroxy-4,6-dimethylpyrimidine in nicarbazin
(Elsevier Science, 2016-01)
The determination of the dissociation constant of 2-hydroxy-4,6-dimethylpyrimidine in nicarbazin was carried out by means of capillary electrophoresis using a dynamic coating of a fused-silica capillary with high-molecular-mass ...
A sensitivity equation for quantitative analysis with multivariate curve resolution-alternating least-squares: Theoretical and experimental approach
(American Chemical Society, 2012-09-11)
A new equation is derived for estimating thesensitivity when the multivariate curve resolution-alternating leastsquares (MCR-ALS) method is applied to second-order multivariatecalibration data. The validity of the expression ...
Thermally induced solid-state transformation of cimetidine. A multi-spectroscopic/chemometrics determination of the kinetics of the process and structural elucidation of one of the products as a stable N3-enamino tautomer
(Elsevier Science, 2015-05)
Exposure of cimetidine (CIM) to dry heat (160-180 °C) afforded, upon cooling, a glassy solid containing new and hitherto unknown products. The kinetics of this process was studied by a second order chemometrics-assisted ...